HTTP Status Code list

Common HTTP Status codes:

200-OK, the server successfully returned to the Web page
-standard response for successful HTTP requests.

301-moved permanently (permanent jump), the requested page has been permanently redirected to the new location.
-This and all of the future requests should is directed to the given.

403-forbidden (no access), the server rejects the request
-Forbidden request (matches a deny filter) = HTTP 403
-the request was a legal request and the server is refusing to respond to it.

404-not Found, the server could not find the requested page.
-The requested resource could is not being found but may is available again in the future.

500-internal Server error (internal server errors)
-Internal Error in Haproxy = HTTP 500
-A generic error message, given when no more specific message is suitable.

502-bad Gateway (Bad Gateway), typically when the gateway server requests the backend service, the backend service does not return the results correctly as the HTTP protocol.
-the server returned an invalid or incomplete response = HTTP 502
-The server was acting as a gateway or proxy and received a invalid response from the upstream server.

503-service unavailable (service is not currently available), may be due to overloading or downtime maintenance.
-No server is available to handle the request + = 503
-The server is currently unavailable (because it was overloaded or down for maintenance).

504-gateway Timeout (gateway timeout), typically when a gateway server requests a backend service, the backend service does not complete the service in a specific time period.
-The server failed to reply in time + = HTTP 504
-The server was acting as a gateway or proxy and do not receive a timely response from the upstream server.

Detailed HTTP status Code Daquan

1XX (Temporary response)
A status code that represents a temporary response and requires the requestor to continue the operation.

the 101 (switching protocol) requestor has asked the server to switch protocols and the server has confirmed and is ready to switch. 

2XX (Success)
Represents the status code that successfully processed the request.

 201 202203  204  205206 (partial content) the server successfully processed a partial GET request.

3XX (redirected)
Indicates that further action is required to complete the request. Typically, these status codes are used for redirection.

 301 302303  304  305307 (Temporary redirect) server currently responds to requests from different locations of the Web page, but the requestor should continue to use the original location for future requests.

4xx (Request error)
These status codes indicate a possible error in the request and hinder the processing of the server.

Code Description HTTP status Code -(Error request) The server does not understand the syntax of the request. HTTP status Code401(Unauthorized) Request authentication is required. The server may return this response for pages that need to log on. HTTP status Code403(Forbidden) The server rejects the request. HTTP status Code404(not found) The requested Web page was not found by the server. HTTP status Code405(method Disabled) Disables the method specified in the request. HTTP status Code406(not accepted) cannot use the requested content attribute to respond to the requested Web page. HTTP status Code407(Requires proxy authorization) This status code is associated with the401(not authorized), but specifies that the requestor should authorize the use of the proxy. HTTP status Code408A timeout occurred while the server was waiting for a request (Request timed out). HTTP status Code409(conflict) The server has a conflict when it finishes the request. The server must include information about the conflict in the response. HTTP status Code410(Deleted) If the requested resource has been permanently deleted, the server returns this response. HTTP status Code411(requires valid length) The server does not accept requests that do not contain a valid Content-Length header field. HTTP status Code412(Prerequisites not met) the server did not meet one of the prerequisites set by the requestor in the request. HTTP status Code413(Request entity is too large) the server cannot process the request because the request entity is too large to exceed the processing power of the server. HTTP status Code414(The requested URI is too long) The requested URI (usually the URL) is too long for the server to process. HTTP status Code415(Unsupported media type) The requested format is not supported by the requested page. HTTP status Code416(the request scope does not meet the requirements) if the page cannot provide the requested scope, the server returns this status code. HTTP status Code417(unmet expectations) the server does not meet the requirements for the "expected" Request header field.

5XX (server error)
These status codes indicate that the server has an internal error while trying to process the request. These errors may be the error of the server itself, not the request.

 501 502503  504  505 (HTTP version not supported) the HTTP protocol version used in the request is not supported by the server.

The above status applies to the status information returned by Web containers such as Tomcat,nginx, and should be remembered for common red flagged status codes. Other knowledge:

HTTP Status Code list